Tracheostomy valves and related methods

ABSTRACT

The embodiments of the present tracheostomy valves include a flexible diaphragm abutting a rib shaped substantially as a flat plate. Opposite the rib, the diaphragm abuts a boss and forms an uninterrupted seal therewith. As the tracheostomized patient inhales, the diaphragm bends about the rib, interrupting the seal and allowing air to flow smoothly into the valve. The features of the various embodiments contribute to a positive seal at all times except during inhalation, and low resistance to airflow through the valve during inhalation.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.13/244,067, filed on Sep. 23, 2011, which is a continuation of U.S.patent application Ser. No. 11/830,573, filed on Jul. 30, 2007 andissued as U.S. Pat. No. 8,051,856 on Nov. 8, 2011, each of which ishereby incorporated by reference in its entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to valves and methods for use withtracheostomized patients.

2. Description of the Related Art

U.S. Pat. No. 4,759,356, the entirety of which is incorporated byreference herein, describes a tracheostomy valve unit. The valve unit issecurable to one end of a tracheostomy tube assembly to regulate airflow through the tube. The valve unit remains closed when thetracheostomized patient exhales, and at all other times except when thepatient inhales. When the patient inhales, the valve opens to allow airto flow through the tracheostomy tube to the patient's lungs.

An outer end of the valve includes a support to which a flexiblediaphragm is secured. The diaphragm selectively seals the valve inresponse to the inhalation and exhalation of the patient. A rivet passesthrough the center of the diaphragm and the center of the support tosecure these two components to one another. The rivet also seats thediaphragm against a seating ring on the support to preload the diaphragmand create an effective closure that maintains a positive, uninterruptedcontact all along the seating ring at all times except when the patientinhales.

When properly manufactured, the tracheostomy valve unit described in the‘356 patent is an effective apparatus for blocking outward air flowthrough the patient's tracheostomy tube, and for allowing inward airflow through the tube. However, the rivet must be precisely placed inorder to preload the diaphragm and create the effective closuredescribed above. If the rivet does not pull the diaphragm far enoughtoward the seating ring the diaphragm will not be properly preloaded andthe valve will not be sealed at rest. On the other hand, if the rivetpulls the diaphragm too far toward the seating ring the diaphragm willbe overloaded and will require too much pressure to open. In extremecases the diaphragm may even wrinkle, which causes gaps to developbetween the diaphragm and the seating ring. The gaps, of course,compromise the sealing ability of the diaphragm.

As described in the ‘356 patent, the process of placing the rivetinvolves a heat-staking step. “The effective length of rivet 20 isestablished during installation by blocking head 20a of the rivet withan adjustable support while at the same time heat-staking end 20c.Adjustment of the adjustable support then compresses rivet 20 and formsheat-staked end 20c, which mounts the diaphragm to support 16 andpreloads diaphragm 18.” (col. 9, 11. 52-58) Unfortunately, theheat-staking is rather imprecise, as the position of the heat-staked end20c is affected by the temperature of the heat-staking apparatus and thelength of time that heat is applied to the heat-staked end 20c. Thesevariables are difficult to control with the precision necessary toproperly place the rivet every time. There is also a tendency for meltedplastic to stick to the tip of the heat-staking apparatus, which furthercomplicates control over the process. Thus, a high percentage of thetracheostomy valve units are rejected during the manufacturing process,which in turn raises the cost of manufacturing the valve units.

SUMMARY OF THE INVENTION

The preferred embodiments of the present tracheostomy valves and relatedmethods have several features, no single one of which is solelyresponsible for their desirable attributes. Without limiting the scopeof these valves and methods as expressed by the claims that follow,their more prominent features will now be discussed briefly. Afterconsidering this discussion, and particularly after reading the sectionentitled “Detailed Description of the Preferred Embodiments,” one willunderstand how the features of the preferred embodiments provideadvantages, which include ease of manufacture, reliable and repeatabledeformation of the diaphragm, smooth airflow through the valve unitduring inhalation, and an uninterrupted seal preventing airflow throughthe valve unit at all times except during inhalation.

One embodiment of the present tracheostomy valves and related methodscomprises a tracheostomy valve unit configured to cooperate with atracheostomy tube insertable within a patient's trachea. The valve unitcomprises a valve body having a first end, a second end and a fluidpassageway extending therethrough. The first end is configured to beoperably connected with the tracheostomy tube. A flexible diaphragm ispositioned within the fluid passageway spaced from the first end of thevalve body. The diaphragm has a first face and a second face oppositethe first face. A rib is positioned within the fluid passageway. Atleast a portion of the rib abuts the first face of the diaphragm. Aspacing between the diaphragm and the valve body first end is greaterthan a spacing between the rib and the valve body first end. At least aportion of the rib defines an imaginary plane that intersects at least aportion of the diaphragm in an imaginary line.

Another embodiment of the present tracheostomy valves and relatedmethods comprises a tracheostomy valve unit configured to cooperate witha tracheostomy tube insertable within a patient's trachea. The valveunit comprises a valve body having a first end, a second end and a fluidpassageway extending therethrough. The first end is configured to beoperably connected with the tracheostomy tube. A rib shaped as asubstantially flat plate is positioned within the fluid passageway andextends between opposite inner surfaces of the valve body along adiameter thereof. A flexible diaphragm is positioned within the fluidpassageway spaced from the first end of the valve body. The diaphragmhas a first face and a second face opposite the first face. At least aportion of an edge of the rib abuts the first face of the diaphragm. Aspacing between the diaphragm and the valve body first end is greaterthan a spacing between the rib and the valve body first end.

Another embodiment of the present tracheostomy valves and relatedmethods comprises a method of alleviating physiological dysfunction andimproving bodily function in a patient who has been subjected totracheostomization, where the dysfunction results from thetracheostomization and the function is impaired by thetracheostomization, the patient having a neck-opening into the patient'strachea, the neck opening being adapted to admit air into the trachea.The method comprises the steps of: (1) inserting into the trachea viathe neck opening a tracheostomy tube, the tracheostomy tube having atracheal end adapted to be received in the trachea, a proximal endadapted to be external to the patient's body, and a fluid passagewayextending therethrough, the fluid passageway having a tube inlet at theproximal end and a tube outlet at the tracheal end in the patient'strachea; (2) inserting into the trachea the tracheostomy tube such thatthe tracheal end is received in the patient's trachea and the proximalend is external to the patient's body, the tube thus being configured toconduct air to the patient's trachea from the inlet to the outlet viathe fluid passageway; (3) operatively securing to the proximal end ofthe tracheostomy tube a tracheostomy valve unit, the tracheostomy valveunit having a first end configured for operative connection to theproximal end of the tracheostomy tube, a second end, a valve unit inletlocated at the second end of the valve unit, conducting means forpermitting airflow therethrough from the valve unit inlet through thevalve unit and then through the tube to the patient's trachea when thepatient inhales, and blocking means making positive, uninterruptedclosure contact with the valve unit inlet and thereby entirely blockingairflow through the conducting means from the tube and through the valveinlet at all times when the patient exhales and at all other timesexcept when the patient inhales; and (4) fluidically connecting thevalve first end to the proximal end of the tracheostomy tube and therebypermitting airflow from the valve unit inlet through the valve unit andthen through the tube inlet to the patient's trachea when the patientinhales and entirely blocking airflow through the conducting means fromthe tube inlet and through the valve unit inlet to the ambient air atall times when the patient exhales and at all other times except whenthe patient inhales. As the patient inhales a pressure difference acrossthe blocking means bends the blocking means around an imaginary lineextending across the blocking means, thereby breaking the positive,uninterrupted closure contact with the valve unit inlet and permittingair to flow from the ambient through the valve unit inlet and into thevalve unit.

Another embodiment of the present tracheostomy valves and relatedmethods comprises a tracheostomy valve unit configured to cooperate witha tracheostomy tube insertable within a patient's trachea. The valveunit comprises a valve body having a proximal end, a distal end and afluid passageway extending therethrough. The proximal end is configuredto be operably connected with the tracheostomy tube. A rib is positionedwithin the fluid passageway adjacent the distal end, the rib beingcontiguous with the valve body. A flexible diaphragm is positionedwithin the fluid passageway distally from the rib. The diaphragm has aproximal face and a distal face. A cap is operably secured to the valvebody distally from the diaphragm. The cap including a seating ring. Atleast a portion of the rib abuts the proximal face of the diaphragm andthe seating ring abuts the distal face of the diaphragm. The rib andseating ring deform the diaphragm to create an uninterrupted positiveseal at a junction between the diaphragm and the seating ring.

BRIEF DESCRIPTION OF THE DRAWINGS

The preferred embodiments of the present tracheostomy valves and relatedmethods, illustrating its features, will now be discussed in detail.These embodiments depict the novel and non-obvious tracheostomy valvesshown in the accompanying drawings, which are for illustrative purposesonly. These drawings include the following figures, in which likenumerals indicate like parts:

FIG. 1 is a front perspective view of one embodiment of the presenttracheostomy valves;

FIG. 2 is an exploded front perspective view of the tracheostomy valveof FIG. 1;

FIG. 3 is an exploded rear perspective view of the tracheostomy valve ofFIG. 1;

FIG. 4 is a front perspective, cross-sectional view of the tracheostomyvalve of FIG. 1;

FIG. 5 is a cross-sectional view of the tracheostomy valve of FIG. 1,taken along the line 5-5 in FIG. 1;

FIG. 6 is a cross-sectional view of the tracheostomy valve of FIG. 1,taken along the line 6-6 in FIG. 1, and illustrating a diaphragm of thevalve in a flexed state as it appears when the patient inhales;

FIG. 7 is a cross-sectional view of a valve body of the tracheostomyvalve of FIG. 1 taken along the line 7-7 of FIG. 8;

FIG. 8 is a front elevational view of the valve body of FIG. 7;

FIG. 9 is a rear elevational view of the valve body of FIG. 7;

FIG. 10 is a front elevational view of a cap of the tracheostomy valveof FIG. 1;

FIG. 11 is a rear elevational view of the cap of FIG. 10;

FIG. 12 is a cross-sectional view of the cap of FIG. 10 taken along theline 12-12 of FIG. 11;

FIG. 13 is a cross-sectional view of another embodiment of the presenttracheostomy valves taken along the line 13-13 of FIG. 14;

FIG. 14 is a front elevational view of the tracheostomy valve of FIG.13;

FIG. 15 is a rear elevational view of the tracheostomy valve of FIG. 13;

FIG. 16 is a cross-sectional view of another embodiment of the presenttracheostomy valves taken along the line 16-16 of FIG. 17;

FIG. 17 is a front elevational view of the tracheostomy valve of FIG.16;

FIG. 18 is a cross-sectional view of another embodiment of the presenttracheostomy valves taken along the line 18-18 of FIG. 19;

FIG. 19 is a front elevational view of the tracheostomy valve of FIG.18; and

FIG. 20 is a rear elevational view of the tracheostomy valve of FIG. 18.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIGS. 1-6 illustrate one embodiment of the present tracheostomy valve.The valve 30 is shaped substantially as a tapered elongate cylinder, andincludes a proximal end 32 and a distal end 34 (FIG. 1). As used herein,the terms proximal and distal refer to proximity to a tracheostomizedpatient. Thus, for example, the proximal end 32 of the valve 30 is sonamed because it is relatively closer to the patient when the valve 30is properly engaged with a tracheostomy tube that is positioned within astoma in a patient.

With reference to FIGS. 2 and 3, the valve 30 comprises a valve body 36,a diaphragm 38 and a cap 40. FIGS. 7-9 illustrate the valve body 36 indetail. In the illustrated embodiment, the valve body 36 comprises,substantially, a tapered cylindrical outer body 42 and a taperedcylindrical inner body 44. An interior portion of the inner body 44defines a fluid passageway 46 (FIG. 7) that conducts air through thevalve 30, as described in detail below.

With reference to FIG. 4, the inner body 44 resides within the outerbody 42, and a distal end 48 of the inner body 44 includes an outwardlyextending flange 50 that merges with an inner surface 52 of the outerbody 42 at a location spaced from the distal end 34 of the outer body42. In the illustrated embodiment, the inner body flange 50 extends atan angle of approximately 45° outward from the inner body 44 and towardthe distal end 34 of the valve 30. Those of ordinary skill in the artwill appreciate that the inner body flange 50 could extend at any anglefrom the inner body 44. However, shallower angles create lesserresistance to airflow past the flange, while steeper angles creategreater resistance. Thus, relatively shallow angles are preferred, and45° provides acceptable airflow. A surface of the flange 50 that facesdistally forms a shoulder 54 that supports a rib 56, as explained indetail below.

With reference to FIG. 7, an outer diameter of the inner body 44 is lessthan an inner diameter of the outer body 42, such that a cylindricalcavity 58 exists between the inner body 44 and the outer body 42. Aplurality of regularly spaced splines 60 (FIGS. 7 and 9) extends acrossthe cavity 58 and joins the inner body 44 to the outer body 42. In theillustrated embodiment, four splines 60 are shown and each spline 60extends from the distal end 48 of the inner body 44 to a location spacedfrom the proximal end 32 of the valve 30 (FIG. 4). However, those ofordinary skill in the art will appreciate that fewer or more splines 60may be provided, and that the splines 60 may extend a shorter or alonger distance along the cavity 58. The splines 60 advantageouslyincrease the rigidity of the valve body 36 and help to maintain theround shape of the valve body 36. However, those of ordinary skill inthe art will appreciate that that no splines need be provided.

With reference to FIG. 7, the wall thickness of the inner body 44increases in the proximal-to-distal direction. Thus, in that samedirection the inner diameter of the inner body 44 gradually decreasesand the outer diameter of the inner body 44 gradually increases. Theinner body 44 is thus configured to mate with a tracheostomy tube (notshown) in a sliding friction fit. In one embodiment the tracheostomytube is received within the inner body 44, while in another embodimentthe inner body 44 is received within the tracheostomy tube. In yetanother embodiment an adapter (not shown) is disposed between the valve30 and the tracheostomy tube so that the inner body 44 and thetracheostomy tube do not directly engage one another. The inner body 44may be sized to mate with commonly used tracheostomy tubes of knowndiameters and wall thicknesses. For example, in one embodiment the innerbody 44 includes a 15 mm ISO taper. However, the inner body 44 may beproduced in a variety of sizes to fit any tracheostomy application.Furthermore, those of ordinary skill in the art will appreciate that insome embodiments the inner body 44 may not include tapered surfaces.

With reference to FIG. 7, in the illustrated embodiment an outer surface62 of the outer body 42 tapers inwardly from the proximal end 32 to thedistal end 34. The tapering facilitates the placement of the valve 30 inline with a ventilator. For example, the proximal end 32 of the valvebody 36 may receive a tracheostomy tube, as described above, and thedistal end 34 of the valve body 36 may receive a tube associated withthe ventilator, with the tube overlapping the distal end 34 in a slidingfriction fit. The outer body 42 may be sized to mate with commonly usedtubes of known diameters and wall thicknesses. For example, in oneembodiment the outer body 42 includes a 22 mm ISO taper. However, theouter body 42 may be produced in a variety of sizes and tapers to fitany application. Furthermore, those of ordinary skill in the art willappreciate that in some embodiments the outer body 42 may not include atapered outer surface 62.

With reference to FIGS. 2 and 7, a proximal end 32 of the outer body 42includes an outwardly extending flange 64. The flange 64 advantageouslyincreases the rigidity of the valve body 36 and helps to maintain theround shape of the valve body 36. However, those of ordinary skill inthe art will appreciate that the flange 64 need not be provided.

With continued reference to FIGS. 2 and 7, the outer body 42 includes aninwardly extending annular ledge 66. The ledge 66 extends around theinside circumference of the outer body 42 and is spaced a short distancefrom the distal end 34. The ledge 66 provides a seat for the cap 40, asexplained in detail below. With reference to FIGS. 2 and 8, a key 68extends inwardly from an inner surface of the outer body 42 at thedistal end 34 thereof. The key 68 mates with a key slot 70 (FIGS. 2 and10) on the cap 40, as explained in detail below.

With reference to FIGS. 2 and 7, a rib 56 extends across the valve body36. The rib 56 is shaped substantially as a flat plate, and extendsbetween inner surfaces of the outer body 42, across the diameterthereof. A distal edge 72 (FIG. 2) of the rib 56 is spaced in theproximal direction from the ledge 66. A proximal edge 74 (FIG. 7) of therib 56 lies in an imaginary plane defined by a proximal edge 76 of theshoulder 54, such that proximal corners 78 of the rib 56 extend alongthe shoulder 54 (FIG. 2). Those of ordinary skill in the art willappreciate that the rib 56 could be shaped and/or configureddifferently. For example, the rib 56 could extend a shorter distance ora longer distance along a length of the valve body 36, and/or the rib 56need not abut the shoulder 54.

With reference to FIGS. 2, 8 and 9, in the illustrated embodiment asubstantially cylindrical post 80 intersects the rib 56. A longitudinalaxis of the post 80 substantially coincides with a longitudinal axis ofthe valve body 36. A diameter of the post 80 is greater than a thicknessof the rib 56. A height of the post 80 is greater than a length of therib 56, such that a distal extension portion 82 (FIG. 2) of the post 80extends distally from the distal edge 72 of the rib 56. The distalextension portion 82 mates with a recess 84 (FIG. 12) in the cap 40, asexplained in detail below. Those of ordinary skill in the art willappreciate that the post 80 could be shaped and/or configureddifferently. For example, the post 80 may be taller or shorter, and/orhave a smaller or larger diameter, and/or have a differentcross-sectional shape.

To either side of the post 80, the distal edge 72 of the rib 56 includesfirst and second biasing protrusions 86. The protrusions 86 bear againstcenter portions of the diaphragm 38 to bias the diaphragm 38 against thecap 40, as described in detail below. The biasing contributes to acomplete, uninterrupted seal around the entirety of the cap 40, asexplained in detail below.

For clarity, and with reference to FIG. 5, the valve body 36, includingthe inner body 44 and the outer body 42, are illustrated as a firstunitary piece, and the rib 56 and the post 80 are illustrated as asecond unitary piece. Those of ordinary skill in the art will appreciatethat the valve body 36 and the rib 56/post 80 may be formed as separatepieces that are, for example, adhered or welded to one another, orsecured by any other suitable means. Those of ordinary skill in the artwill also appreciate that the valve body 36, the rib 56 and the post 80may be formed as a single, unitary piece.

In one embodiment, the valve body 36 may be constructed of a plastic oranother similar material. In one such embodiment the valve body 36 isconstructed of Acrylonitrile Butadiene Styrene (ABS plastic). Those ofordinary skill in the art will appreciate that the valve body 36 couldbe constructed of alternative materials, such as acrylics, polymers(such as polypropylene and polyethylene) and metals. The valve body 36may be made by any of a variety of processes, such as molding, injectionmolding, casting and machining.

With reference to FIGS. 2 and 3, the diaphragm 38 comprises a relativelythin disk with a central aperture 88. The aperture 88 is configured andpositioned to receive the distal extension portion 82 of the post 80,such that the diaphragm 38 seats upon the protrusions 86. Portions ofthe diaphragm 38 may contact the distal edge 72 of the rib 56.

In the illustrated embodiment, the diaphragm 38 is circular. However,those of ordinary skill in the art will appreciate that the diaphragm 38could have any shape that is configured to cooperate with the valve body36 and the cap 40 to create a seal at or near the distal end 34 of thevalve 30. The diaphragm 38 is preferably flexible so that it can deformas the patient inhales, thereby breaking the seal and allowing air toflow through the valve 30. The diaphragm 38 is also preferably capableof forming a seal when in contact with the cap 40. In one embodiment,the diaphragm 38 is constructed of silicone. However, those of ordinaryskill in the art will appreciate that other materials could be usedinstead.

FIGS. 10-12 illustrate in detail the cap 40. The cap 40 resembles awheel, and includes a central hub 90, an outer rim 92, and a pluralityof spokes 94, 96 extending between the hub 90 and the rim 92. In theillustrated embodiment, six spokes 94, 96 are provided, and neighboringspokes 94, 96 are separated by approximately 60°. However, those ofordinary skill in the art will appreciate that fewer or more spokescould be provided, and that the spokes need not be regularly spaced.Furthermore, in the illustrated embodiment two of the spokes 94 arerelatively thick, and four of the spokes 96 are relatively thin.However, those of ordinary skill in the art will appreciate that more ofthe spokes may be relatively thick, or more of the spokes may berelatively thin. In at least some of the spokes 94, 96, it isadvantageous for a cross-section of the spoke to taper outwardly in thedistal-to-proximal direction. This configuration reduces resistance toairflow through the cap 40, as described in detail below.

In the illustrated embodiment, the hub 90 is circular and includes acylindrical recess 84 in a proximal surface thereof (FIG. 12). Therecess 84 receives the distal extension portion 82 of the post 80 on thevalve body 36 in a mating engagement, as described in detail below. Thecross-sectional shape and/or depth of the recess 84 may be varied toenable the recess 84 to mate with the post 80. A distal, outer edge 98of the hub 90 includes a taper that reduces resistance to airflowthrough the cap 40, as described in detail below. A distal face of thehub 90 includes a boss 100 having a central depression 102.

In the illustrated embodiment, the rim 92 is circular and includes anirregular cross-section (FIG. 12) having a flat outer surface 104(facing away from the hub 90) and a tapered inner surface 106 (facingtoward the hub 90). However, those of ordinary skill in the art willappreciate that the rim 92 could have virtually any shape, such as oval,elliptical or square. Those of ordinary skill in the art will alsoappreciate that the rim 92 could have virtually any cross-sectionalshape. However, the tapered inner surface 106, in which the innerdiameter of the rim 92 decreases in the distal-to-proximal direction,advantageously reduces resistance to airflow through the cap 40, asdescribed in detail below.

In the illustrated embodiment, the outer surface of the rim 92 includesa key slot 70 (FIG. 10) that mates with the key 68 on the valve body 36,as shown in FIGS. 1 and 2. The mating key 68 and key slot 70 ensure thatthe cap 40 is properly aligned with the valve body 36. When properlyaligned, the wider spokes 94 on the cap 40 align with the rib 56. Thisconfiguration reduces the resistance to airflow through the valve 30, asdescribed in detail below. Those of ordinary skill in the art willappreciate that neither the key 68 nor the key slot 70 need be provided.Those of ordinary skill in the art will also appreciate that more keysand mating key slots could be provided on the valve body 36 and the cap40, respectively. Those of ordinary skill in the art will alsoappreciate that the locations of the key(s) and key slot(s) could bereversed. That is, the cap 40 could be provided with one or more keys,and the valve body 36 could be provided with one or more mating keyslots.

In the illustrated embodiment, a proximal surface 108 of the rim 92includes an annular boss 110 (FIG. 12). The boss 110 is located adjacentthe inner surface 106 of the rim 92, and extends entirely around the rim92. In the assembled valve 30, the boss 110 bears against outer portionsof the diaphragm 38, as described in detail below. The boss 110 thusdeforms and pre-loads the diaphragm 38 to create an uninterrupted sealaround the entire boss 110, as described in detail below.

The cap 40 may be constructed of the same material as the valve body 36,or of a different material. For example, the cap 40 may be constructedof any of the materials described above with respect to the valve body36. However, those of ordinary skill in the art will appreciate that thecap 40 could be constructed of other materials.

With reference to FIGS. 1-6, in the assembled valve 30 the distal end 34of the valve body 36 receives the diaphragm 38 with the distal extensionportion 82 (FIG. 5) of the post 80 extending through the aperture 88.With particular reference to FIG. 5, the cap 40 nests within the distalend 34, sandwiching the diaphragm 38 between the rib 56 and the cap 40.An outer edge of the proximal surface 108 of the rim 92 abuts the ledge66 on the valve body 36. The ledge 66 thus helps to positively locatethe cap 40 within the valve body 36. Reliable and repeatable location ofthe cap 40 helps to ensure that the diaphragm 38 is properly biasedagainst the boss 110 on the cap 40, and advantageously contributes to alow rejection rate during the manufacturing process. The outer surface104 of the rim 92 may engage the inner surface of the valve body 36 in afriction fit to help maintain the cap 40 within the valve body 36.Alternatively, or in addition, adhesive may be applied during themanufacturing process in any region where the cap 40 abuts the valvebody 36. The adhesive may be UV curable, for example. Alternatively, orin addition, the abutting surfaces of the cap 40 and the valve body 36may be welded.

As shown in FIGS. 4 and 5, the distal extension portion 82 of the post80 extends into the recess 84 in the proximal face of the hub 90. Thedistal extension portion 82 may engage the recess 84 in a friction fitto help maintain the cap 40 within the valve body 36. Alternatively, orin addition, adhesive may be applied to the distal extension portion 82and/or within the recess 84 during the manufacturing process.Alternatively, or in addition, the distal extension portion 82 may bewelded within the recess 84.

FIG. 5 illustrates a cross-sectional view of the valve 30. The sectionplane of FIG. 5 passes through the rib 56 and coincides with animaginary plane defined by the rib 56, as shown by the line 5-5 inFIG. 1. The diaphragm 38 occupies a space between the rib 56 and the cap40. In the illustrated embodiment, a thickness of the diaphragm 38 isgreater than a perpendicular distance between a first imaginary planethat abuts the boss 110 and a second imaginary plane that abuts thebiasing protrusions 86. The boss 110 thus bears against outer portionsof the distal face 112 of the diaphragm 38 while the biasing protrusions86 bear against central portions of the proximal face 114 of thediaphragm 38. The forces applied to the diaphragm 38 by the boss 110 andthe biasing protrusions 86 balance one another and bend the diaphragm 38out of plane. The diaphragm 38 is in a state of equilibrium in which theproximal face 114 is slightly concave and the distal face 112 isslightly convex. Furthermore, the continuous force applied to thediaphragm 38 by the boss 110 helps to maintain a positive anduninterrupted seal at the junction of the boss 110 and the diaphragm 38.This seal prevents air from leaking outward through the valve 30, whichprovides several advantages, including improved speech, olfaction,oxygenation and swallowing, decreased nasal and oral secretions andlessening of chronic infections.

In one embodiment, the bias applied to the diaphragm 38 is equivalent toapproximately 8 to 15 mm of water head. This amount of bias effectivelyseats the diaphragm 38 against the boss 110 to maintain positive,uninterrupted contact at the junction therewith. In one embodiment, abias of 8 to 15 mm of water head can be obtained with a diaphragm 38constructed of silicone having a hardness of 40 Shore A, the diaphragmhaving a diameter of approximately 0.75″ and a thickness ofapproximately 0.015″, where the center of the diaphragm 38 is displacedapproximately 0.002″ to 0.003″ out of plane relative to the edge of thediaphragm 38.

The configuration of the present valve 30 advantageously overcomes theshortcomings of the tracheostomy valve unit described in U.S. Pat. No.4,759,356. As outlined above, the manufacturing process for the valvedescribed in the ‘356 patent involves a heat-staking step. This step isaffected by the temperature of the heat-staking apparatus and the lengthof time that heat is applied to the heat-staked end. These variables aredifficult to control with the precision necessary to properly place therivet every time. In the present valve 30, there is no heat-stakingstep. Thus, proper loading of the diaphragm 38 depends only upon thedimensional tolerances of the valve components. These tolerances areeasier to control than the variables involved in heat-staking. Thus, thepresent valve 30 achieves a lower rejection rate during manufacturing,which in turn lowers the costs of manufacturing the valve 30.

FIG. 6 illustrates a cross-sectional view of the valve 30. The sectionplane of FIG. 6 passes through the rib 56 and is perpendicular to animaginary plane defined by the rib 56, as shown by the line 6-6 inFIG. 1. In FIG. 6, the diaphragm 38 is deformed as it appears when thepatient inhales. As the patient inhales he or she creates a net pressuredifference across the diaphragm 38, with a greater pressure bearingagainst the distal face 112. The force of the air bearing against thedistal face 112 deforms the diaphragm 38 and breaks the seal at thejunction of the boss 110 and the diaphragm 38. Air thus flows around thediaphragm 38 and into the valve 30 through the distal end 34, asillustrated by the arrows in FIG. 6.

Because the rib 56 is substantially planar, an imaginary plane definedby the rib 56 intersects the diaphragm 38 in an imaginary line, and thediaphragm 38 bends about this line as the patient inhales. The diaphragm38 thus deforms in a predictable and repeatable way. At the moment justprior to inhalation, the air pressure on the distal face 112 is uniformover the entire exposed area of the distal face 112. Thus, as inhalationbegins the air bearing against the distal face 112 creates a bendingmoment for the diaphragm 38 about the rib 56. The magnitude of thebending moment is greatest at the two locations on diaphragm 38 thatabut the boss 110 and are spaced farthest from the rib 56, since thepressure on the distal face is uniform, and the longest moment armsoccur at these two points 116 (FIG. 4). In the illustrated embodiment,since the rib 56 is substantially planar and the boss 110 is circular,the two points 116 on the boss 110 spaced farthest from the rib 56coincide with an imaginary line drawn perpendicular to the rib 56 andpassing through the post 80. Thus, as the patient inhales the sealbetween the diaphragm 38 and the boss 110 always breaks first at thesetwo points 116, and the diaphragm 38 bends in a smooth arc around therib 56, as illustrated in FIG. 6. This predictable and repeatablebreaking and bending provides low resistance to the valve opening. Thelow resistance in turn contributes to low resistance to airflow throughthe valve and reduces or eliminates any sounds made by the diaphragm 38.When the patient stops inhaling, the diaphragm 38 returns to itsoriginal configuration of FIG. 5, thereby resealing the valve 30 at thejunction with the boss 110.

As described above, an imaginary plane defined by the rib 56 intersectsthe diaphragm 38 in an imaginary line, and the diaphragm 38 bends aboutthis line as the patient inhales. (FIG. 6) Therefore, air flowing intothe valve 30 through the distal end 34 passes to either side of the rib56. Any obstructions, such as spokes 94, 96, on either side of the rib56 will increase resistance to airflow. By contrast, spokes 94, 96 thatalign with the rib 56 provide little, if any, additional impedance toairflow beyond that which is already created by the rib 56 itself.Therefore, the greatest resistance to airflow through the valve 30 isprovided when none of spokes 94, 96 are aligned with the rib 56, and theresistance can be reduced if the narrower spokes 96 align with the rib56, and the least resistance can be achieved if the two wider spokes 94align with the rib 56. As described above, the key 68 on the valve body36 and the key slot 70 on the cap 40 ensure that the wider 94 spokesalign with the rib 56.

The least resistance to airflow through the valve 30 is achieved whenthe airflow is laminar. Turbulence will cause the diaphragm 38 toflutter, which will disrupt the airflow. The shapes of some portions ofthe cap 40 facilitate laminar airflow. For example, the inner surface106 of the rim 92 (facing toward the hub 90) tapers inward so that theinner diameter of the rim 92 decreases in the distal-to-proximaldirection (FIGS. 6 and 12). Also, side edges 118 of the spokes taperoutward in the distal-to-proximal direction (FIGS. 10 and 11), and thehub 90 includes a rounded distal outer edge 98 (FIGS. 6 and 12). Each ofthese features reduces resistance to airflow, thereby facilitatingsmooth, laminar airflow through the cap 40.

FIGS. 13-15 illustrate another embodiment of the present tracheostomyvalves. The valve 150 of FIGS. 13-15 is substantially similar to thevalve 30 illustrated in FIGS. 1-12, and includes a valve body 152, a rib154, a post 156, a diaphragm 158 and a cap 160. For clarity, thediaphragm 158 has been illustrated as if it were opaque. However, thoseof ordinary skill in the art will appreciate that the diaphragm 158could be transparent. The valve body 152 includes an outer valve body162 and an inner valve body 164, with a tapered cylindrical cavity 166formed between these two members at a proximal end 168 of the valve body152. A plurality of regularly spaced splines 170 extends across thecavity 166 and joins the inner body 164 to the outer body 162. The rib154 is shaped and configured similarly to the rib 56 described above,and includes first and second biasing protrusions 172.

With reference to FIGS. 13 and 14, the cap 160 is shaped and configuredsimilarly to the cap 40 described above, and includes a hub 174, a rim176 and a plurality of spokes 178 extending between the hub 174 and therim 176. In the cap 160 of FIGS. 14-16, however, only four spokes 178are provided, and neighboring spokes are spaced by approximately 90°.Those of ordinary skill in the art will appreciate that fewer or morespokes 178 could be provided, and that the spokes 178 need not beregularly spaced. Furthermore, in the illustrated embodiment each of thespokes 178 is of a uniform thickness. However, those of ordinary skillin the art will appreciate that some of the spokes may have thicknessesthat differ from the thickness of one or more other spokes. In theembodiment of FIGS. 14-16, the cap 160 is illustrated with no key slot,and the valve body 152 is illustrated with no key. However, those ofordinary skill in the art will appreciate that a key slot and a key maybe provided on these components.

FIGS. 16 and 17 illustrate another embodiment of the presenttracheostomy valves. The valve 200 of FIGS. 16 and 17 is substantiallysimilar to the valve 150 illustrated in FIGS. 13-15. However, in thevalve 200 of FIGS. 16 and 17 the cap 202 includes an outwardly extendingflange 204 at a distal end 206 thereof that extends outward adjacent adistal face 208 of the valve body 152. The cap 202 nests within thedistal end 210 of the valve body 152, and seats upon a ledge 212 thatextends around the valve body 152. However, the ledge 212 is spaced alesser distance from the distal face 208 of the valve body 152, ascompared to the valve 150 illustrated in FIGS. 13-15.

FIGS. 18-20 illustrate another embodiment of the present tracheostomyvalves. As with the embodiments described above, the valve 250 of FIGS.18-20 includes a valve body 252, a rib 254 with a post 256 and biasingprotrusions 258, a diaphragm 260 and a cap 262. However, theconfigurations of some of these components are substantially differentfrom the embodiments described above. For example, the valve body 252does not comprise an outer body and an inner body. Rather, the valvebody 252 includes a substantially cylindrical proximal portion 264, anda distal portion 266 that flares outwardly and forms a bowl-shapeddistal end of the valve body 252. A proximal end 268 of the valve body252 is configured to receive an end of a tracheostomy tube (not shown)in an overlapping friction fit. An outer surface of the tube may engagean inner surface of the proximal end 268, or an inner surface of thetube may engage an outer surface of the proximal end 268. The proximalend 268 may include a taper, along the inside diameter or along theoutside diameter or along both, to enhance the friction fit.

With reference to FIG. 18, the cap 262 comprises a wall that tapersslightly inwardly from a proximal end 270 to a distal end 272. At thedistal end 272, the wall curls inwardly so that a cross-section of thewall resembles a J. The proximal end 270 of the cap 262 adjoins thedistal portion 266 of the valve body 252. The distal portion 266includes an annular ledge 274 extending around an outer surface thereof.The ledge 274 is formed by a step down in the wall thickness of thevalve body 252. The cap 262 also includes a ledge 276 that is formed bya step down in its wall thickness. However, the ledge 276 on the cap 262is formed around an inner surface thereof. Thus, the cap 262 mates withthe distal portion 266 of the valve body 252 with the relativelythin-walled portions of each piece overlapping one another.

The cap 262 further includes a beveled outer edge 278 adjacent theproximal end 270. When the cap 262 and valve body 252 are assembled, thebevel 278 the ledge 274 on the valve body 252 together form asubstantially V-shaped groove that extends around the outsidecircumference of the valve 250. The groove provides an advantageouslocation to apply a bead of adhesive to hold the cap 262 and valve body252 together. However, those of ordinary skill in the art willappreciate that adhesive need not be used. The cap 262 and valve body252 may be secured to one another through other techniques, such as afriction fit, ultrasonic welding, etc. Alternatively, adhesive may beapplied in other areas, such as along the abutting faces of therelatively thin-walled portions of each piece.

The curled distal end 272 of the cap 262 forms a ring-shaped surface 280that faces in the proximal direction and bears against the diaphragm260. As in the previous embodiments, the diaphragm 260 is locatedbetween the cap 262 and the rib 254, with the post 256 extending throughan aperture in the diaphragm 260 and the protrusions 258 bearing againstthe diaphragm 260. Portions of the diaphragm 260 may contact a distaledge 282 of the rib 254. The curled end surface 280 of the cap 262 andthe protrusions 258 bias the diaphragm 260 into the concave/convexconfiguration described in detail above with respect to the previousembodiments.

With reference to FIG. 18, the curled distal end 272 of the cap 262tapers inwardly in the distal-to-proximal direction, similar to the cap40 of FIGS. 10-12. The taper advantageously facilitates laminar airflow, as discussed above with respect to the cap 40 of FIGS. 10-12. Withreference to FIG. 19, in the illustrated embodiment the cap 262 includessix evenly spaced spokes 284, 286, with two of the spokes 284 beingrelatively thick and the remaining four spokes 286 being relativelythin. The spokes 284, 286 may include tapered side edges similar tothose discussed above with respect to the cap 40 of FIGS. 10-12. Thetapered side edges advantageously facilitate laminar air flow, as alsodiscussed above. While in FIGS. 18-20 the wider spokes 284 areillustrated as being not aligned with the rib 254, those of ordinaryskill in the art will appreciate the spokes 284, 286 may be aligned withthe rib 254 in order to achieve the air flow advantages discussed abovewith respect to the valve 30 of FIG. 1.

SCOPE OF THE INVENTION

The above presents a description of the best mode contemplated forcarrying out the present tracheostomy valves and related methods, and ofthe manner and process of making and using them, in such full, clear,concise, and exact terms as to enable any person skilled in the art towhich they pertain to make and use these tracheostomy valves and relatedmethods. These tracheostomy valves and related methods are, however,susceptible to modifications and alternate constructions from thatdiscussed above that are fully equivalent. Consequently, thesetracheostomy valves and related methods are not limited to theparticular embodiments disclosed. On the contrary, these tracheostomyvalves and related methods cover all modifications and alternateconstructions coming within the spirit and scope of the tracheostomyvalves and related methods as generally expressed by the followingclaims, which particularly point out and distinctly claim the subjectmatter of the tracheostomy valves and related methods.

What is claimed is:
 1. A tracheostomy valve unit configured to cooperatewith a tracheostomy tube insertable within a trachea of a patient, thevalve unit comprising: a valve body including a first end, a second end,a sidewall extending between the first end and the second end, and afluid passageway extending from the first end to the second end, thefirst end operably connectable with a tracheostomy tube, the valve bodycomprising an inner body and an outer body connected to the inner bodyby a shoulder, the shoulder being spaced from the first end of the valvebody; a flexible diaphragm in the fluid passageway and spaced from thefirst end of the valve body, the diaphragm defining a plane; a rib inthe fluid passageway, the rib shaped substantially as a flat plate, atleast a first portion of the rib abutting the diaphragm, at least asecond portion of the rib abutting an inner surface of the outer bodysubstantially orthogonal to the diaphragm, the rib defining a planesubstantially perpendicular to the plane of the diaphragm; and a postintegrally formed with the rib and extending distally from the rib,wherein the diaphragm comprises an aperture, and wherein the postextends through the aperture.
 2. The valve unit of claim 1, wherein theplane of the rib intersects a center of the diaphragm.
 3. The valve unitof claim 1, further comprising a cap cooperating with the second end ofthe valve body, wherein the cap includes an annular boss abutting thediaphragm.
 4. The valve unit of claim 3, wherein the cap includes anouter rim, an inner hub, and a plurality of spokes extending between thehub and the rim.
 5. The valve unit of claim 4, wherein at least aportion of the rim seats within the fluid passageway.
 6. The valve unitof claim 3, wherein an inner surface of the fluid passageway includes anannular ledge, and wherein the rim abuts the ledge.
 7. A valve unitcomprising: a proximal end; a distal end; an inner body having an innersurface inwardly obliquely angled towards the proximal end, the innersurface sloping from a first end of the inner body to a second end ofthe inner body, an interior portion of the inner body defining a fluidpassageway; an outer body inwardly obliquely angled towards the distalend; a substantially planar rib extending at least partially across theinner body, a distal portion of the rib comprising biasing protrusions,a distal edge of the rib being proximate the distal end of the valveunit: an inner ledge proximate to the distal end; a cap proximate thedistal end of the valve unit and having an outermost periphery insidethe valve body and comprising a rim abutting the inner ledge, the capcomprising an annular boss; a diaphragm in contact with and between theboss of the cap and the biasing protrusions of the rib, the ribsubstantially transverse to the diaphragm; and a post integrally formedwith the rib and extending distally from the rib, wherein the diaphragmcomprises an aperture, and wherein the post extends through theaperture.
 8. The valve unit of claim 7, further comprising a pluralityof splines between the inner body and the outer body.
 9. The valve unitof claim 7, further comprising a flange extending radially outward froma distal end of the outer body.
 10. The valve unit of claim 7, whereinthe rib is integral with the inner body.
 11. The valve unit of claim 7,wherein the rib extends fully across the inner body.
 12. The valve unitof claim 7, wherein the cap comprises a plurality of spokes, at leastsome said spokes being thicker than other said spokes, wherein thethicker spokes are aligned with the rib.
 13. The valve unit of claim 12,wherein the cap includes a key configured to align the thicker spokesand the rib.
 14. The valve unit of claim 7, wherein the cap comprisessurfaces configured to facilitate laminar flow through the valve unit.15. The valve unit of claim 7, wherein the cap comprises a hubcomprising a recess, and wherein the post extends into the recess.